# Oscillator

Discussion in 'General Electronics Discussion' started by electronic123, Oct 26, 2017.

1. ### electronic123

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0
Oct 21, 2017
Hi

I'm learning about oscillator and looking for a really simple circuit to see how it works

i would appreciate if someone send a super simple circuit

thank you

2. ### kellys_eye

4,275
1,147
Jun 25, 2010
What kind of oscillator?

Audio, RF, sine, square???? There are many different types and each used for specific purposes. Your request is too vague to answer with certainty.

3. ### Alec_t

2,970
805
Jul 7, 2015
Here you go :

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4. ### kellys_eye

4,275
1,147
Jun 25, 2010
Apparently not!

LOL

5. ### dorke

2,342
665
Jun 20, 2015
Here is an even simpler one.
Simpler to explain and understand.
Any number of odd gates can be used, you can use 1,3,5 from an hex schmidt-trigger and notice the effect on the oscillation period.

Obviously, You should use an oscilloscope to test it.

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6. ### FuZZ1L0G1C

368
118
Mar 25, 2014

aka Multivibrator.
Very simple operation -
One base switches its transistor on first, due to tolerance imbalances between components. (eg Q1).
That capacitor, C1 discharges through Q1 c-e junction, completing ground-path for C1.
Due to discharge, other plate of C1, connected to Q2b, gets pulled negative, switching Q2 off.
This allows C2 to charge up as no path to ground.
Meanwhile, already discharged C1 no longer negative so R2 feeds a positive bias to Q2 base until Q2 conducts, discharging C2 and switching Q1b off. So the cycle continues....
Note: Waveform on collectors is not true square due to charging capacitors.
The RC values set the time constant for each half, so adjustment of mark-space ratio is possible.
For a truer square wave, emitter-base couple a third transistor to the multivibrator.
Q3b must go to Q1e or Q2e. Then load on Q3c.

7. ### CDRIVEHauling 10' pipe on a Trek Shift3

4,960
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May 8, 2012
One of my first oscillators.
Chris

2,515
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Jun 10, 2015

ak

9. ### dorke

2,342
665
Jun 20, 2015
Single relay, electoro-mechanical Oscillator.

10. ### CDRIVEHauling 10' pipe on a Trek Shift3

4,960
652
May 8, 2012
Dork, you beat me to it. I added a flyback diode and cap to clean up the output. Though excluding them makes an effective alarm clock event. Ya just need to add two wires taped to your body.

Chris

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